setup.py: Add missing wpull.backport to packages.

Closes chfoo/wpull#159
http.stream: Don't drain on final write to avoid "Connection lost".
phantomjs: Don't use wait_for to avoid losing items from queue.
connection.py: Close ourselves on timeout to avoid FD leak.
collections.OrderedDefaultDict: Fix recursion error during copy.

Don't copy and paste from the internet without testing them throughly.

Closes chfoo/wpull#160
http.web: Fix stuck in loop on 307/308 redirects.
builder,proxy.py: Set rewrite=True.

Closes chfoo/wpull#161
http.request: Account for empty reasons and the 0 status code.

Closes chfoo/wpull#165
Use manhole to create a Unix domain socket-accessible REPL

Connect to it with:

rlwrap nc -U /tmp/manhole-PID
Never fsync... who has time for that?
Use a beautifulsoup4 compatible with Python 3.5